Experimental study on mechanical mechanism of retractable drilling shaft lining under the condition of stratum subsidence

Aiming at the fractured mechanism of mine shaft lining under the condition of stratum subsiding, a new type of retractable drilling shaft lining structure was proposed. The model test results show that the shaft lining can be compressed and vertical additional forces forced on the shaft lining can be accordingly released. Based on the test results, the design method of vertical bearing capacity of the retractable drilling shaft lining was obtained. The results of this paper were successful applied in four shafts in Huaibei mine area.